10586.29 is the One … For Now

The tortured way in which Microsoft finally arrived at a “final” build of Windows 10 version 1511 for PCs, tablets, phones and other devices is an interesting story in its own right. More interesting, perhaps, is that the 29th rendition of this build, or 10586.29, was just silently rolled out indiscriminately to Windows 10 Mobile-based handsets almost as soon as it was released. And that, folks, is unique, though I’d warn fans not to get too excited, as carriers can of course still block software updates going forward. And probably will.

How Microsoft was able to get 10586.29 past watchdogs at the normally reluctant wireless carriers is unclear. But there are clues, I think, in Microsoft’s recent blog post about the initial 10586.29 release for Windows Insiders (i.e. “beta testers”).

“As our partners and Microsoft ship new Windows 10 mobile devices and existing devices are upgraded to Windows 10, all of our users will start to see more updates coming through Windows Update,” Microsoft’s Gabe Aul explained. “These will be addressing feedback we receive from our Windows Insiders and new Windows 10 users.”

Now read that first bit again.

All of our users will start to see more updates coming through Windows Update.

All users. Not just Insiders, but all users. Interesting.

Aul goes on to describe 10586.29 as a cumulative update, and not a new build of Windows 10. On PCs and tablets, that is true enough: This update is delivered through Windows Update like any other update, and only the truly nerdish would even notice that in installing it, the build number is updated from whatever 10586.x build number you were on to 10586.29.

But on Windows phone, things are quite different. There, all updates require a reboot, and this “cumulative update” is delivered and installed just like a full new build, with the resulting “spinning gears” screen and an interminable wait.

Aul stressed again and again, however, that this was not a new build—e.g. something carriers might actively block—but was rather just a cute little minor thing not to be trifled with.

“The first thing you will notice with this Cumulative Update is it will use the minor version for differentiating between each version as these builds only contain fixes,” he wrote. “So this build will appear as 10586.29.”

Only fixes. No new features. Nothing for a carrier to be concerned with. You know, since new features arrive via app updates, not OS updates.

My assumption is that Microsoft has pulled a quick one here, and has essentially fooled the carriers into letting this one through, perhaps because some of those “fixes” are security-related. Or perhaps there was an agreement with the few remaining carriers now supporting Windows phone to just let this first one fly since the phones were in fact delivered with incomplete, pre-release-quality software. And no one wanted to miss the holidays.

Whatever the reason, let’s not get too excited. The carriers are still the carriers, and they can still block updates as they see fit. But with a bigger percentage of Windows phones being sold unlocked now, it’s perhaps true that fewer updates will be blocked overall going forward, since Microsoft allegedly controls updates to those devices.